Your choice depends on the operating temperature range and other criteria such as:
-required mechanical execution i.e. naked chip, SMD, epoxy coated, surface sensor or glass sealed
-lead length and diameter
Decide on the value of R25 you need .Refer to the R/T characteristic of the sensor series you chose in step 1.In these characteristic curves, each sensor in the series is distinguished by its R25-value.Choose an R25-value to give a resistance at your average temperature of operation of between 1kΩ and 100kΩ or the value that best fits your electronic measuring circuit voltage and current range.
Determine the tolerance on R25.
Using the R/T tables of the respective datasheets.
For other important requirements such as response time and length of component ,ect